1. Field of the Invention
The present invention relates to a method and device for retransmitting packets in a wired/wireless network, and more particularly, to a method and device for efficiently detecting packets for which transmission has failed in a wired/wireless network and transmitting a negative acknowledgement message (NACK) only once for a block of packets for which transmission has failed many times, so that it is possible to efficiently retransmit packets.
2. Description of the Related Art
In a wired/wireless network, a transmission apparatus transmits packets, and when a reception apparatus does not receive the transmitted packets the transmission apparatus retransmits the packets. The wired/wireless network includes an Ethernet, an Ad-hoc network, and a sensor network. In each network technology, retransmission is needed, and a packet transmission rate is affected by a retransmission method.
A method of transmitting and receiving an acknowledgement message (ACK) is generally used as a packet retransmission method. For example, in the IEEE 802.15.4 standard for the sensor network, when an ACK is not received within a predetermined time after transmitting a packet, retransmission is attempted.
However, in the method of transmitting the explicit ACK for each packet, the ACK transmission and reception occupies transmission media, and thus there is a problem in that a data packet transmission rate decreases. In addition, due to an ACK algorithm, the amount of overhead calculation increases.
In order to increase the packet transmission rate, a method of using an ACK algorithm which has high performance and is complex is used. However, in this method, the overhead of the ACK algorithm increases, and thus there is a problem in that the method cannot be used in a subminiature device such as a sensor node.
An invention “Method and Apparatus for Transmitting Block ACK Frame” disclosed in U.S. Patent Publication No. 20060048034 (publication date 2006 Mar. 2) proposes a method and apparatus for transmitting a block ACK. In this method, a block ACK is transmitted to a transmission apparatus using a compressed bitmap format, and the size of the block ACK is reduced, so that transmission time and error probability can be reduced. However, a compression algorithm and bitmap manipulation are required, and calculation complexity is high, and thus there is a problem in that the method cannot be used in the subminiature device.